PROJECT SUMMARY CLINICAL CORE The goals of the Clinical Core are 1) to accrue the necessary samples and associated clinical data from Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) patients and healthy subject cohorts to support the research projects of the proposed ME/CFS Collaborative Research Center (ME/CFS CRC), and 2) to engage the ME/CFS patient and advocate community through online platforms and outreach. The Clinical Core will be based at the Bateman Horne Center of Excellence (BHC), a patient-centered research and clinical care center focused specifically on improving the clinical management of ME/CFS and fostering research into biomarker discovery and mechanisms of disease. The Core will implement standardized processes for subject recruitment, enrollment and clinical specimen collection, clinical data acquisition (in coordination with the Data Management and Coordination Center) and subject follow up. It will implement clinical evaluation to objectively quantify orthostatic intolerance, unrefreshing sleep and cognitive efficiency. It will also oversee storage and distribution of clinical samples to ME/CFS CRC investigators. The Clinical Core will also leverage BHC's expertise in patient engagement and its extensive network of patient partners and advocates to facilitate community support for the proposed research and retention of recruited subjects. A community engagement coordinator will work with enrolled ME/CFS patients to regularly self-track, through online App in collaboration with ?We are Curious? platform, their symptoms and treatments, along with daily activity, dietary interventions, and environmental exposures, providing support and guidance throughout to facilitate retention throughout the study period. The Clinical Core will be led by Drs. Lucinda Bateman and Suzanne D. Vernon, both deeply experienced and respected members of the ME/CFS clinical and research communities. Under their oversight, the Clinical Core will address the theme of the ME/CFS CRC by enhancing patient engagement and subject participation, improving sample and clinical data collection, ensuring efficient selection of subjects, and facilitating acquisition of robust and relevant patient parameters. The Specific Aims are: 1) To identify, refer and enroll patients with new-onset ME/CFS along with age, race and sex-matched controls for longitudinal clinical tracking and serial sample acquisition; 2) To conduct clinical evaluations to objectively define fatigue and daily function, post- exertional malaise, unrefreshing sleep, cognitive impairment and orthostatic intolerance using common data elements, standardized questionnaires and devices; 3) To oversee storage and sharing of clinical phenotype and biological sample data in coordination with the Data Management and Coordination Center (DMCC); and 4) To partner with We are Curious and MEAction groups to develop questionnaires, tags and tracking systems that reflect patient symptoms and experiences with ME/CFS, and bridge patient partners and the clinical and scientific teams through education and outreach.